PDCD1 and malaria: For example, CD8+ T-cell exhaustion can be characterized by a number of cell surface markers including PD-1, Tim-3, LAG-3, and IL-10 plasma levels (Osuch et al., 2020), and earlier studies already identified that PD-1 dependent exhaustion of CD8+ T cells in malaria facilitated a chronic disease state (Horne-Debets et al., 2013).